TL;DR ( at the start )
Whoever is forced to approach, generally loses if the other knows how to deal with the approaches.
/end TL;DR
You really know the matchup. lol Then again, your purple name doesn't suprise me.
At my recent tournament, I didn't really face anyone worth mentioning... lol... the best G&W I faced there was probably Princess Aura
whom I 3 stocked, then barely beat on Norfair (I was about to JV 3 stock then she started learning the matchup more and did what you did. Avoid the camping, and approach when you find an opening. XD)
However, if the Snake knows how to deal with your approaches.... you get pretty screwed sadly. :/
Also 1 dthrow is basically guaranteed % if the Snake can react fast enough. ( I will admit normal getup > up-B is pretty hard to react to... but still possible) Snake just needs to shield, and punish whatever you do. (Standup with grab, roll behind us with ftilt, roll away, with ftilt/dash attack getup attack with grab)
If we face away from you and pull a grenade, it is extremely difficult (may be near impossible) to Bair AND avoid hitting the grenade... Bair is your best move to avoid hitting the grenade... <_<
When the G&W is at 112%, on any neutral besides Yoshi's Island, this SHOULD KO (I haven't tested Lylat :x it's a CP where I am...) so after trading enough damage/racking it up just wait for the right time to utilt.
The G&W however, has a distinct advantage on some stages once they get the lead... G&W can do really well at avoiding Snake's camping, so get the lead and just avoid us and you force an approach. G&W, ***** our approaches.... :/ but this is only on a few select stages..... but still something to take note of.
All of this is from personal experience.... :x which, until I face someone like you, or another good G&W probably means far less then what it's worth. D=
I'm probably one of the few Snake's who's favorite matchup is Falco as well... <_< but similiar to G&W... I haven't faced any pro Falco's....